Field of the Invention
The present invention relates to an application execution apparatus equipped with a virtual machine controlling an installed application, a control method therefor, and a storage medium storing a control program therefor.
Description of the Related Art
An MFP (Multifunction Peripheral) is known as an application execution apparatus into which a virtual machine module (hereinafter referred to as a “virtual machine”, simply), such as a Java (registered trademark) VM (Virtual Machine), is built. A plurality of extended application modules (hereinafter referred to as an “extended application”, simply) that extend functions can be installed in an MFP, and a virtual machine controls installed extended applications. When an extended application is installed in an MFP, an icon showing the extended application is displayed on an operation screen of the MFP, for example. When a user selects the icon concerned, the MFP performs a display control process that displays an image of a GUI (Graphical User Interface) of the extended application (hereinafter referred to as an “extended application GUI”) corresponding to the selected icon. In a general display control process, a virtual machine draws a background of an extended-application GUI with a background color set up beforehand by an extended application, and then, the extended application draws the remaining extended-application GUI other than the background.
However, some extended applications that are installed in an MFP draw the entire extended-application GUI including a background at the time of displaying the extended-application GUI. Although such an extended application draws the entire extended-application GUI including a background, a virtual machine may also draw the background of the extended-application GUI according to the specification of the system. In such a case, since the background of the extended-application GUI is drawn multiple times, a flicker at the time of displaying extended-application GUI becomes remarkable. On the other hand, there is a proposed technique that prohibits a virtual machine from drawing a background in a drawing process for an extended-application GUI (for example, see Japanese Laid-Open Patent Publication (Kokai) No. 2006-171274 (JP 2006-171274A)).
However, the technique of JP 2006-171274A mentioned above causes a problem that an incomplete extended-application GUI that lacks a background is displayed when an extended application of which specification defines that a virtual machine draws a background of an extended-application GUI is executed.